1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Modifications by Kumar Gala (galak@kernel.crashing.org) to support
4 * E500 Book E processors.
5 *
6 * Copyright 2004,2010 Freescale Semiconductor, Inc.
7 *
8 * This file contains the routines for initializing the MMU
9 * on the 4xx series of chips.
10 * -- paulus
11 *
12 * Derived from arch/ppc/mm/init.c:
13 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
14 *
15 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
16 * and Cort Dougan (PReP) (cort@cs.nmt.edu)
17 * Copyright (C) 1996 Paul Mackerras
18 *
19 * Derived from "arch/i386/mm/init.c"
20 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
21 */
22
23 #include <linux/signal.h>
24 #include <linux/sched.h>
25 #include <linux/kernel.h>
26 #include <linux/errno.h>
27 #include <linux/string.h>
28 #include <linux/types.h>
29 #include <linux/ptrace.h>
30 #include <linux/mman.h>
31 #include <linux/mm.h>
32 #include <linux/swap.h>
33 #include <linux/stddef.h>
34 #include <linux/vmalloc.h>
35 #include <linux/init.h>
36 #include <linux/delay.h>
37 #include <linux/highmem.h>
38 #include <linux/memblock.h>
39
40 #include <asm/prom.h>
41 #include <asm/io.h>
42 #include <asm/mmu_context.h>
43 #include <asm/mmu.h>
44 #include <linux/uaccess.h>
45 #include <asm/smp.h>
46 #include <asm/machdep.h>
47 #include <asm/setup.h>
48 #include <asm/paca.h>
49
50 #include <mm/mmu_decl.h>
51
52 unsigned int tlbcam_index;
53
54 #define NUM_TLBCAMS (64)
55 struct tlbcam TLBCAM[NUM_TLBCAMS];
56
57 struct tlbcamrange {
58 unsigned long start;
59 unsigned long limit;
60 phys_addr_t phys;
61 } tlbcam_addrs[NUM_TLBCAMS];
62
tlbcam_sz(int idx)63 unsigned long tlbcam_sz(int idx)
64 {
65 return tlbcam_addrs[idx].limit - tlbcam_addrs[idx].start + 1;
66 }
67
68 #ifdef CONFIG_FSL_BOOKE
69 /*
70 * Return PA for this VA if it is mapped by a CAM, or 0
71 */
v_block_mapped(unsigned long va)72 phys_addr_t v_block_mapped(unsigned long va)
73 {
74 int b;
75 for (b = 0; b < tlbcam_index; ++b)
76 if (va >= tlbcam_addrs[b].start && va < tlbcam_addrs[b].limit)
77 return tlbcam_addrs[b].phys + (va - tlbcam_addrs[b].start);
78 return 0;
79 }
80
81 /*
82 * Return VA for a given PA or 0 if not mapped
83 */
p_block_mapped(phys_addr_t pa)84 unsigned long p_block_mapped(phys_addr_t pa)
85 {
86 int b;
87 for (b = 0; b < tlbcam_index; ++b)
88 if (pa >= tlbcam_addrs[b].phys
89 && pa < (tlbcam_addrs[b].limit-tlbcam_addrs[b].start)
90 +tlbcam_addrs[b].phys)
91 return tlbcam_addrs[b].start+(pa-tlbcam_addrs[b].phys);
92 return 0;
93 }
94 #endif
95
96 /*
97 * Set up a variable-size TLB entry (tlbcam). The parameters are not checked;
98 * in particular size must be a power of 4 between 4k and the max supported by
99 * an implementation; max may further be limited by what can be represented in
100 * an unsigned long (for example, 32-bit implementations cannot support a 4GB
101 * size).
102 */
settlbcam(int index,unsigned long virt,phys_addr_t phys,unsigned long size,unsigned long flags,unsigned int pid)103 static void settlbcam(int index, unsigned long virt, phys_addr_t phys,
104 unsigned long size, unsigned long flags, unsigned int pid)
105 {
106 unsigned int tsize;
107
108 tsize = __ilog2(size) - 10;
109
110 #if defined(CONFIG_SMP) || defined(CONFIG_PPC_E500MC)
111 if ((flags & _PAGE_NO_CACHE) == 0)
112 flags |= _PAGE_COHERENT;
113 #endif
114
115 TLBCAM[index].MAS0 = MAS0_TLBSEL(1) | MAS0_ESEL(index) | MAS0_NV(index+1);
116 TLBCAM[index].MAS1 = MAS1_VALID | MAS1_IPROT | MAS1_TSIZE(tsize) | MAS1_TID(pid);
117 TLBCAM[index].MAS2 = virt & PAGE_MASK;
118
119 TLBCAM[index].MAS2 |= (flags & _PAGE_WRITETHRU) ? MAS2_W : 0;
120 TLBCAM[index].MAS2 |= (flags & _PAGE_NO_CACHE) ? MAS2_I : 0;
121 TLBCAM[index].MAS2 |= (flags & _PAGE_COHERENT) ? MAS2_M : 0;
122 TLBCAM[index].MAS2 |= (flags & _PAGE_GUARDED) ? MAS2_G : 0;
123 TLBCAM[index].MAS2 |= (flags & _PAGE_ENDIAN) ? MAS2_E : 0;
124
125 TLBCAM[index].MAS3 = (phys & MAS3_RPN) | MAS3_SX | MAS3_SR;
126 TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_SW : 0);
127 if (mmu_has_feature(MMU_FTR_BIG_PHYS))
128 TLBCAM[index].MAS7 = (u64)phys >> 32;
129
130 /* Below is unlikely -- only for large user pages or similar */
131 if (pte_user(__pte(flags))) {
132 TLBCAM[index].MAS3 |= MAS3_UX | MAS3_UR;
133 TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_UW : 0);
134 }
135
136 tlbcam_addrs[index].start = virt;
137 tlbcam_addrs[index].limit = virt + size - 1;
138 tlbcam_addrs[index].phys = phys;
139 }
140
calc_cam_sz(unsigned long ram,unsigned long virt,phys_addr_t phys)141 unsigned long calc_cam_sz(unsigned long ram, unsigned long virt,
142 phys_addr_t phys)
143 {
144 unsigned int camsize = __ilog2(ram);
145 unsigned int align = __ffs(virt | phys);
146 unsigned long max_cam;
147
148 if ((mfspr(SPRN_MMUCFG) & MMUCFG_MAVN) == MMUCFG_MAVN_V1) {
149 /* Convert (4^max) kB to (2^max) bytes */
150 max_cam = ((mfspr(SPRN_TLB1CFG) >> 16) & 0xf) * 2 + 10;
151 camsize &= ~1U;
152 align &= ~1U;
153 } else {
154 /* Convert (2^max) kB to (2^max) bytes */
155 max_cam = __ilog2(mfspr(SPRN_TLB1PS)) + 10;
156 }
157
158 if (camsize > align)
159 camsize = align;
160 if (camsize > max_cam)
161 camsize = max_cam;
162
163 return 1UL << camsize;
164 }
165
map_mem_in_cams_addr(phys_addr_t phys,unsigned long virt,unsigned long ram,int max_cam_idx,bool dryrun)166 static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt,
167 unsigned long ram, int max_cam_idx,
168 bool dryrun)
169 {
170 int i;
171 unsigned long amount_mapped = 0;
172
173 /* Calculate CAM values */
174 for (i = 0; ram && i < max_cam_idx; i++) {
175 unsigned long cam_sz;
176
177 cam_sz = calc_cam_sz(ram, virt, phys);
178 if (!dryrun)
179 settlbcam(i, virt, phys, cam_sz,
180 pgprot_val(PAGE_KERNEL_X), 0);
181
182 ram -= cam_sz;
183 amount_mapped += cam_sz;
184 virt += cam_sz;
185 phys += cam_sz;
186 }
187
188 if (dryrun)
189 return amount_mapped;
190
191 loadcam_multi(0, i, max_cam_idx);
192 tlbcam_index = i;
193
194 #ifdef CONFIG_PPC64
195 get_paca()->tcd.esel_next = i;
196 get_paca()->tcd.esel_max = mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY;
197 get_paca()->tcd.esel_first = i;
198 #endif
199
200 return amount_mapped;
201 }
202
map_mem_in_cams(unsigned long ram,int max_cam_idx,bool dryrun)203 unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx, bool dryrun)
204 {
205 unsigned long virt = PAGE_OFFSET;
206 phys_addr_t phys = memstart_addr;
207
208 return map_mem_in_cams_addr(phys, virt, ram, max_cam_idx, dryrun);
209 }
210
211 #ifdef CONFIG_PPC32
212
213 #if defined(CONFIG_LOWMEM_CAM_NUM_BOOL) && (CONFIG_LOWMEM_CAM_NUM >= NUM_TLBCAMS)
214 #error "LOWMEM_CAM_NUM must be less than NUM_TLBCAMS"
215 #endif
216
mmu_mapin_ram(unsigned long base,unsigned long top)217 unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top)
218 {
219 return tlbcam_addrs[tlbcam_index - 1].limit - PAGE_OFFSET + 1;
220 }
221
flush_instruction_cache(void)222 void flush_instruction_cache(void)
223 {
224 unsigned long tmp;
225
226 if (IS_ENABLED(CONFIG_E200)) {
227 tmp = mfspr(SPRN_L1CSR0);
228 tmp |= L1CSR0_CFI | L1CSR0_CLFC;
229 mtspr(SPRN_L1CSR0, tmp);
230 } else {
231 tmp = mfspr(SPRN_L1CSR1);
232 tmp |= L1CSR1_ICFI | L1CSR1_ICLFR;
233 mtspr(SPRN_L1CSR1, tmp);
234 }
235 isync();
236 }
237
238 /*
239 * MMU_init_hw does the chip-specific initialization of the MMU hardware.
240 */
MMU_init_hw(void)241 void __init MMU_init_hw(void)
242 {
243 flush_instruction_cache();
244 }
245
adjust_total_lowmem(void)246 void __init adjust_total_lowmem(void)
247 {
248 unsigned long ram;
249 int i;
250
251 /* adjust lowmem size to __max_low_memory */
252 ram = min((phys_addr_t)__max_low_memory, (phys_addr_t)total_lowmem);
253
254 i = switch_to_as1();
255 __max_low_memory = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM, false);
256 restore_to_as0(i, 0, 0, 1);
257
258 pr_info("Memory CAM mapping: ");
259 for (i = 0; i < tlbcam_index - 1; i++)
260 pr_cont("%lu/", tlbcam_sz(i) >> 20);
261 pr_cont("%lu Mb, residual: %dMb\n", tlbcam_sz(tlbcam_index - 1) >> 20,
262 (unsigned int)((total_lowmem - __max_low_memory) >> 20));
263
264 memblock_set_current_limit(memstart_addr + __max_low_memory);
265 }
266
setup_initial_memory_limit(phys_addr_t first_memblock_base,phys_addr_t first_memblock_size)267 void setup_initial_memory_limit(phys_addr_t first_memblock_base,
268 phys_addr_t first_memblock_size)
269 {
270 phys_addr_t limit = first_memblock_base + first_memblock_size;
271
272 /* 64M mapped initially according to head_fsl_booke.S */
273 memblock_set_current_limit(min_t(u64, limit, 0x04000000));
274 }
275
276 #ifdef CONFIG_RELOCATABLE
277 int __initdata is_second_reloc;
relocate_init(u64 dt_ptr,phys_addr_t start)278 notrace void __init relocate_init(u64 dt_ptr, phys_addr_t start)
279 {
280 unsigned long base = kernstart_virt_addr;
281 phys_addr_t size;
282
283 kernstart_addr = start;
284 if (is_second_reloc) {
285 virt_phys_offset = PAGE_OFFSET - memstart_addr;
286 kaslr_late_init();
287 return;
288 }
289
290 /*
291 * Relocatable kernel support based on processing of dynamic
292 * relocation entries. Before we get the real memstart_addr,
293 * We will compute the virt_phys_offset like this:
294 * virt_phys_offset = stext.run - kernstart_addr
295 *
296 * stext.run = (KERNELBASE & ~0x3ffffff) +
297 * (kernstart_addr & 0x3ffffff)
298 * When we relocate, we have :
299 *
300 * (kernstart_addr & 0x3ffffff) = (stext.run & 0x3ffffff)
301 *
302 * hence:
303 * virt_phys_offset = (KERNELBASE & ~0x3ffffff) -
304 * (kernstart_addr & ~0x3ffffff)
305 *
306 */
307 start &= ~0x3ffffff;
308 base &= ~0x3ffffff;
309 virt_phys_offset = base - start;
310 early_get_first_memblock_info(__va(dt_ptr), &size);
311 /*
312 * We now get the memstart_addr, then we should check if this
313 * address is the same as what the PAGE_OFFSET map to now. If
314 * not we have to change the map of PAGE_OFFSET to memstart_addr
315 * and do a second relocation.
316 */
317 if (start != memstart_addr) {
318 int n;
319 long offset = start - memstart_addr;
320
321 is_second_reloc = 1;
322 n = switch_to_as1();
323 /* map a 64M area for the second relocation */
324 if (memstart_addr > start)
325 map_mem_in_cams(0x4000000, CONFIG_LOWMEM_CAM_NUM,
326 false);
327 else
328 map_mem_in_cams_addr(start, PAGE_OFFSET + offset,
329 0x4000000, CONFIG_LOWMEM_CAM_NUM,
330 false);
331 restore_to_as0(n, offset, __va(dt_ptr), 1);
332 /* We should never reach here */
333 panic("Relocation error");
334 }
335
336 kaslr_early_init(__va(dt_ptr), size);
337 }
338 #endif
339 #endif
340
